1. Scope of the Invention
The invention pertains to the linkage device between two successive vehicles --railroad or road --where communication is made possible as a result of the use of bellows or platforms that are noise- and weather-proof. It concerns a deformable device, the purpose of which is to allow, by vertical and/or horizontal movements, deformations between the floors of successive vehicles and is more particularly interesting when the number of linked vehicles is greater than two, because many solutions of the prior art do not apply to this configuration.
2. Description of the Prior Art
Usually, linkage between the different vehicle bodies --especially with respect to bramways --is ensured by swiveling around a vertical axis of a kind of intercommunication turret, in which the cylindrical walls, the fairly plane ceiling and the horizontal floor ensure material continuity of the walls, by rotating around an axis that is perpendicular to the floor of each linked vehicle, the swiveling of a floor in relation to that of the interconnecting compartment occurs along two circle arcs that slide one on the other.
Patent FR 2 357 409 describes an interesting embodiment for such kinematics: the two halves of the interconnecting compartment are connected to one another by a horizontal axis, which is located close to the floor, which makes it possible to ensure the material continuity of the floors from one vehicle to the other with a hinge at the horizontal transversal axis which is preferably placed on the load bearing cross-member of a central bogie. The result is a link, of the cardanic type, with three perpendicular axes between the vehicles. The rolling borsion must be absorbed then by the suspensions of the end bogies, if the track is uneven. This device displays the disadvantage of not being applicable, for mechanical reasons, to a train consisting of more than two cars that travel the warped and twisted tracks of urban or mountain railways for instance.
Patent EP 0 134 202 describes another embodiment of the interconnecting compartment when the chassis of the adjacent vehicles have only one common pivot point; the interconnecting compartment which is represented by two halves which each include a semi-circular floor, is oriented by a device which bisects the angle between the two cars. Those two floors of the interconnecting compartment allow for buckling movements between the floors of the adjacent vehicles, even if their number is greater than two, provided that the floors of the interconnecting compartment are connected by an elastically deformable floor, which is not described in the cited document.
In patent EP 0 181 294, of FIAT, the buckling movement of a rigid floor is allowed by a diagonally extending flexible axis. Patent FR 2 573 714 of FAIVELEY recommends a deformable floor, supported by transverse bars which are fixed at their opposite ends by means of articulated parallelograms. Such a floor, which has to endure the enormous deflections --especially those resulting from shearing motions --between vehicles to which it is secured by its ends, must be very flexible and, basically, supported by additional transverse bars which would fill cells, which cells are essential to enable deformation.
Analysis of the prior art apparently reveals the need for a floor in an interconnecting compartment between railroad or road vehicles that can bear loads while being continuous and that can accomodate for misalignements caused by differences in operating levels of the vehicles, buckling motions between the vehicles and small changes in the connecting distance between vehicles. Because of the development of technologies, it would seem also necessary that this type of deformable floor for interconnecting compartment applies to/trains which comprise more than two vehicles.